Fiber for medical antibacterial fabric and preparation method therefor

ABSTRACT

A preparation method of fibers for medical antibacterial fabric includes cooling an antibacterial polyester melt by ring-blowing after extruded from a trilobal spinneret hole on a spinneret, and manufacturing a fully drawn yarn (FDY), then performing a relaxation heat treatment to obtain the fiber. The shapes and sizes of three leaves from different trilobal spinneret holes are the same; wherein all the trilobal spinneret holes are distributed in concentric circles, and the direction of the shortest leaf in each trilobal spinneret hole is randomly distributed. The prepared fiber has a three-dimensional crimp shape and includes antibacterial polyester monofilaments with trilobal cross-section. The fiber has mechanical performance indices as a crimp shrinkage of 26-29%, a crimp stability of 78-82%, a shrinkage elongation of 55-62%, a crimp elastic recovery rate of 70-75%, a breaking strength of 2.4-2.6 cN/dtex, an elongation at break of 55.0±5.0%, and a monofilament fineness of 1.00-1.50 dtex.

CROSS REFERENCE TO THE RELATED APPLICATIONS

This application is the national phase entry of InternationalApplication No. PCT/CN2020/095716, filed on Jun. 12, 2020, which isbased upon and claims priority to Chinese Patent Application No.201911386331.2, filed on Dec. 29, 2019, the entire contents of which areincorporated herein by reference.

TECHNICAL FIELD

The present invention belongs to the field of polyester fiber, and moreparticularly, relates to one type of fiber for medical antibacterialfabric and preparation method therefor.

BACKGROUND

With the enhancement of medical and health services, more and moremedical textiles have been produced. The requirements of medicaltextiles are different from those of clothing textiles, mainly reflectedin antibacterial properties and practicality. The clothing textilesgenerally use a variety of raw materials to meet consumers' demand forcomfortable wearing, but most medical textiles are disposable discards,so that choosing raw materials as few as possible can reduce processingand costs. Polyester fibers are widely used in medical textiles due to avariety of modifications and deformations, but the elasticity inpolyester fibers generally comes from the false-twist texturing processor the bicomponent spinning process, both of which increase the costgreatly.

Therefore, it is of great significance to develop one type of fiber formedical fabric with simple process and crimp shrinkage.

SUMMARY

The primary object of the present invention is to provide one type offiber for medical antibacterial fabric and preparation method therefor,so as to solve the problem of complicated processing process ofpolyester fiber in medical fabric to achieve crimp shrinkage in theprior art.

To this end, the technical schemes of the invention are as follows:

The method for preparing a fiber for medical antibacterial fabric,comprising that cooling an antibacterial polyester melt by ring-blowingafter extruded from a trilobal spinneret hole on a spinneret, andmanufacturing a fully drawn yarn (FDY) according to an FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment;

wherein a ratio of lengths of three leaves from the same trilobalspinneret hole is 1.0:(1.5-2.5):(1.5-2.5), while the widths of threeleaves are the same, wherein the ratio of the length to the width of theshortest leaf is (2.5-3.5):1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same;

wherein all the trilobal spinneret holes are distributed in concentriccircles, and the direction of the shortest leaf in each trilobalspinneret hole is randomly distributed;

That is, the spinneret is equipped with multiple trilobal spinneretholes, each trilobal spinneret hole contains leaf I, leaf II, and leafIII, and the leaf I is the shortest of the three leaves in all thedifferent trilobal spinneret holes; the ratio of lengths of leaf I, leafII, and leaf III from the same trilobal spinneret hole is1.0:(1.5-2.5):(1.5-2.5), while the widths of three leaves are the same,and the ratio of the length to the width of leaf I is (2.5-3.5):1; inthe same trilobal spinneret hole, the angle between center lines of leafI and leaf II is 120°, the angle between center lines of leaf II andleaf III is 120°, and the angle between center lines of leaf I and leafIII is 120°; the shapes and sizes of three leaves from differenttrilobal spinneret holes are the same, and the direction of leaf I ineach trilobal spinneret hole is randomly distributed;

The following preferred technology program is presented to give adetailed description for this invention.

In the method for preparing a fiber for medical antibacterial fabric,wherein the antibacterial polyester melt has an intrinsic viscosity of0.50-0.55 dL/g;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent with a content of 100-300 ppm ofsilver ions;

wherein the FDY process involves technological parameters: a spinningtemperature of 270-280° C., a cooling temperature of 20-25° C., acooling wind speed of 1.80-2.30 m/s, a godet roller 1 speed of 1800-2000m/min, a godet roller 1 temperature of 85-95° C., a godet roller 2 speedof 2700-2900 m/min, a godet roller 2 temperature of 150-170° C., and awinding speed of 2640-2830 m/min;

wherein the relaxation heat treatment has a temperature of 90-120° C.,and a time of 20-30 min.

The fiber for medical antibacterial fabric is prepared by any one of theabove methods, wherein the prepared fiber for medical antibacterialfabric has a three-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section.

Prepared through the preferred technology program mentioned above,wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices measured according to GB/T6506-2001 as a crimpshrinkage of 26-29%, a crimp stability of 78-82%, a shrinkage elongationof 55-62%, and a crimp elastic recovery rate of 70-75%.

wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices: a breaking strength of 2.4-2.6 cN/dtex, anelongation at break of 55.0±5.0%, and a monofilament fineness of1.00-1.50 dtex.

The principle of the present invention is as follows:

The fiber for medical antibacterial fabric in the present invention isprepared according to the FDY process, which is extruding anantibacterial polyester melt from a trilobal spinneret hole with unequallengths, while cooling by ring-blowing; due to the asymmetric structureof the trilobal spinneret hole, the surface of the leaf first facing thewind in contact with the cooling wind is the entire surface of the leaf,and the surfaces of the other two leaves in contact with the coolingwind are only the windward surfaces; therefore the cooling speed of themelt at different positions in the cross-section is different afterextruding the fiber, specially during spinning, the cooling wind speedis between 1.80-2.30 m/s, wherein the high speed makes the part close tothe air outlet cool faster, and the part far from the air outlet coolslower. When one of the three leaves of the trilobal spinneret holedirectly facing the cooling air, the melt of the leaf cools quickly,while the rest of the trilobal spinneret hole cools slowly, which ismore easily drawn and thinner under the tension of drafting, and itsstress is more concentrated, wherein the fiber with asymmetric stressand thickness in the cross-section has three-dimensional crimpproperties during heat treatment or stretching, and curls well with ahigh fiber elastic recovery rate.

Moreover, in a bundle of filaments, the crimp directions of themonofilaments are inconsistent, because all the trilobal spinneret holesare distributed in concentric circles, and the direction of the shortestleaf in each trilobal spinneret hole is randomly distributed, then thedirection of stress asymmetry is also different, and the direction ofcrimp is different, therefore, the monofilaments with inconsistent crimpdirections will produce “out-of-order” in a bundle of filaments, makingthe bundle of filaments feel more fluffy and plump.

Benefits

(1) The method for preparing a fiber for medical antibacterial fabric inthe present invention, uses a spinneret with asymmetric trilobalspinneret hole for the FDY spinning process, resulting in asymmetricalstresses in the cross-section of the fiber during cooling, making thefibers for medical antimicrobial fabric have three-dimensionalself-crimping properties.

(2) The fiber for medical antibacterial fabric in the present invention,has stable crimp shrinkage after relaxation heat treatment, realizingcrimp elasticity of single-component polyester fiber without false-twisttexturing process.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the structure of the trilobal spinnerethole in the present invention;

FIG. 2 is a schematic diagram of the distribution of the trilobalspinneret holes on a spinneret in the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Based on above mentioned method, the following embodiments are carriedout for further demonstration in the present invention. It is to beunderstood that these embodiments are only intended to illustrate theinvention and are not intended to limit the scope of the invention. Inaddition, it should be understood that after reading the contentsdescribed in the present invention, those technical personnel in thisfield can make various changes or modifications to the invention, andthese equivalent forms also fall within the scope of the claims attachedto the application.

The shapes and distributions of trilobal spinneret holes on thespinneret in the present invention are shown in FIGS. 1-2, wherein thespinneret hole on the spinneret is trilobal, wherein a ratio of lengthsof three leaves from the same trilobal spinneret hole is1.0:(1.5-2.5):(1.5-2.5), while the widths of three leaves are the same,wherein the ratio of the length to the width of the shortest leaf is(2.5-3.5):1, and the angle between center lines of two adjacent leavesis 120°; wherein the shapes and sizes of three leaves from differenttrilobal spinneret holes are the same; wherein all the trilobalspinneret holes are distributed in concentric circles, and the directionof the shortest leaf in each trilobal spinneret hole is randomlydistributed.

FIGS. 1-2 are for illustration only and should not be construed aslimiting the present invention.

Example 1

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5.4dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:1.7:1.5, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 3.3:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 24, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are10°, 60°, 2°, 30°, 90°, 15°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°, 10°,100°, 106°, 100°, 41°, 80°, 65°, 2°, 50°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 100 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 109° C. and a time of 21minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 278° C., a cooling temperature of 23° C., a cooling windspeed of 2.19 m/s, a godet roller 1 speed of 1960 m/min, a godet roller1 temperature of 92° C., a godet roller 2 speed of 2800 m/min, a godetroller 2 temperature of 163° C., and a winding speed of 2740 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 26%, a crimp stability of80%, a shrinkage elongation of 57%, and a crimp elastic recovery rate of70%; a breaking strength of 2.4 cN/dtex, an elongation at break of 60%,and a monofilament fineness of 1.10 dtex.

Example 2

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5.5dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:1.5:1.9, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 2.8:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 24, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are28°, 162°, 64°, 3°, 6°, 105°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°,10°, 100°, 106°, 100°, 41°, 80°, 65°, 2°, 50°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 300 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 109° C. and a time of 20minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 278° C., a cooling temperature of 23° C., a cooling windspeed of 2.19 m/s, a godet roller 1 speed of 1970 m/min, a godet roller1 temperature of 92° C., a godet roller 2 speed of 2820 m/min, a godetroller 2 temperature of 168° C., and a winding speed of 2760 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 26%, a crimp stability of80%, a shrinkage elongation of 58%, and a crimp elastic recovery rate of70%; a breaking strength of 2.45 cN/dtex, an elongation at break of 58%,and a monofilament fineness of 1.20 dtex.

Example 3

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5.4dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:2.0:2.5, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 3.5:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 30, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are10°, 60°, 2°, 30°, 90°, 15°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°, 10°,100°, 106°, 100°, 41°, 80°, 65°, 2°, 50°, 28°, 162°, 64°, 3°, 6°, 105°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 290 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 104° C. and a time of 23minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 277° C., a cooling temperature of 23° C., a cooling windspeed of 2.12 m/s, a godet roller 1 speed of 1930 m/min, a godet roller1 temperature of 91° C., a godet roller 2 speed of 2780 m/min, a godetroller 2 temperature of 161° C., and a winding speed of 2720 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 27%, a crimp stability of78%, a shrinkage elongation of 62%, and a crimp elastic recovery rate of71%; a breaking strength of 2.48 cN/dtex, an elongation at break of 56%,and a monofilament fineness of 1.28 dtex.

Example 4

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5.4dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:1.6:2.0, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 2.8:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 36, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are10°, 60°, 2°, 30°, 90°, 15°, 28°, 162°, 64°, 3°, 6°, 105°, 121°, 93°,161°, 123°, 75°, 129°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°, 10°, 100°,106°, 100°, 41°, 80°, 65°, 2°, 50°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 295 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 98° C. and a time of 24minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 276° C., a cooling temperature of 21° C., a cooling windspeed of 2.04 m/s, a godet roller 1 speed of 1930 m/min, a godet roller1 temperature of 90° C., a godet roller 2 speed of 2780 m/min, a godetroller 2 temperature of 159° C., and a winding speed of 2720 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 29%, a crimp stability of82%, a shrinkage elongation of 59%, and a crimp elastic recovery rate of75%; a breaking strength of 2.5 cN/dtex, an elongation at break of 55%,and a monofilament fineness of 1.36 dtex.

Example 5

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5.2dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:2.5:2.4, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 2.7:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 24, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are152°, 96°, 54°, 100°, 175°, 75°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°,10°, 100°, 106°, 100°, 41°, 80°, 65°, 2°, 50°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 121 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 97° C. and a time of 24minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 273° C., a cooling temperature of 21° C., a cooling windspeed of 2.01 m/s, a godet roller 1 speed of 1890 m/min, a godet roller1 temperature of 89° C., a godet roller 2 speed of 2770 m/min, a godetroller 2 temperature of 158° C., and a winding speed of 2710 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 29%, a crimp stability of78%, a shrinkage elongation of 55%, and a crimp elastic recovery rate of74%; a breaking strength of 2.55 cN/dtex, an elongation at break of 54%,and a monofilament fineness of 1.44 dtex.

Example 6

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:2.2:2.5, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 3:1, and the angle between center lines of two adjacentleaves is 120°; wherein the shapes and sizes of three leaves fromdifferent trilobal spinneret holes are the same; wherein the spinneretis equipped with a circle of equally spaced trilobal spinneret holes,the number of which is 24, and taking the central axis of the shortestleaf of one of the trilobal spinneret holes as the reference line, allthe central axises of the shortest leaves of other trilobal spinneretholes are at a certain angle with the reference line, along theclockwise direction, the included angles of the inferior angles are166°, 40°, 23°, 138°, 112°, 55°, 180°, 53°, 174°, 142°, 131°, 87°, 49°,90°, 65°, 5°, 74°, 161°, 30°, 158°, 45°, 109°, 23°, 47°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 193 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 97° C. and a time of 27minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 271° C., a cooling temperature of 20° C., a cooling windspeed of 2 m/s, a godet roller 1 speed of 1880 m/min, a godet roller 1temperature of 88° C., a godet roller 2 speed of 2770 m/min, a godetroller 2 temperature of 153° C., and a winding speed of 2710 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 29%, a crimp stability of78%, a shrinkage elongation of 58%, and a crimp elastic recovery rate of73%; a breaking strength of 2.56 cN/dtex, an elongation at break of 53%,and a monofilament fineness of 1.50 dtex.

Example 7

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:1.5:2.0, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 2.9:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 48, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are10°, 60°, 2°, 30°, 90°, 15°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°, 10°,100°, 106°, 100°, 41°, 80°, 65°, 2°, 50°, 166°, 40°, 23°, 138°, 112°,55°, 180°, 53°, 174°, 142°, 131°, 87°, 49°, 90°, 65°, 5°, 74°, 161°,30°, 158°, 45°, 109°, 23°, 47°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 201 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 90° C. and a time of 30minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 270° C., a cooling temperature of 20° C., a cooling windspeed of 1.8 m/s, a godet roller 1 speed of 1800 m/min, a godet roller 1temperature of 85° C., a godet roller 2 speed of 2700 m/min, a godetroller 2 temperature of 150° C., and a winding speed of 2640 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 28%, a crimp stability of82%, a shrinkage elongation of 61%, and a crimp elastic recovery rate of72%; a breaking strength of 2.59 cN/dtex, an elongation at break of 52%,and a monofilament fineness of 1.00 dtex.

Example 8

A method for preparing a fiber for medical antibacterial fabric,comprising:

(1) cooling an antibacterial polyester melt (intrinsic viscosity of 5.5dL/g) by ring-blowing after extruded from a trilobal spinneret hole on aspinneret; wherein a ratio of lengths of three leaves from the sametrilobal spinneret hole is 1.0:2.0:2.5, while the widths of three leavesare the same, wherein the ratio of the length to the width of theshortest leaf is 2.5:1, and the angle between center lines of twoadjacent leaves is 120°; wherein the shapes and sizes of three leavesfrom different trilobal spinneret holes are the same; wherein thespinneret is equipped with a circle of equally spaced trilobal spinneretholes, the number of which is 24, and taking the central axis of theshortest leaf of one of the trilobal spinneret holes as the referenceline, all the central axises of the shortest leaves of other trilobalspinneret holes are at a certain angle with the reference line, alongthe clockwise direction, the included angles of the inferior angles are10°, 60°, 2°, 30°, 90°, 15°, 22°, 90°, 1°, 3°, 170°, 40°, 45°, 30°, 10°,100°, 106°, 100°, 41°, 80°, 65°, 2°, 50°;

wherein the antibacterial polyester mainly consists of polyester andantibacterial agents dispersed in it, wherein the antibacterial agent isa silver-based antibacterial agent RHA-02 with a content of 202 ppm ofsilver ions;

(2) manufacturing a fully drawn yarn according to the FDY process, thenthe fiber for medical antibacterial fabric is prepared after arelaxation heat treatment at a temperature of 120° C. and a time of 20minutes;

wherein the FDY process involves technological parameters as a spinningtemperature of 280° C., a cooling temperature of 25° C., a cooling windspeed of 2.3 m/s, a godet roller 1 speed of 2000 m/min, a godet roller 1temperature of 95° C., a godet roller 2 speed of 2900 m/min, a godetroller 2 temperature of 170° C., and a winding speed of 2830 m/min;

wherein the prepared fiber for medical antibacterial fabric has athree-dimensional crimp shape, and comprises a plurality ofantibacterial polyester monofilaments with trilobal cross-section;wherein the fiber for medical antibacterial fabric comprises mechanicalperformance indices as a crimp shrinkage of 28%, a crimp stability of82%, a shrinkage elongation of 58%, and a crimp elastic recovery rate of72%; a breaking strength of 2.6 cN/dtex, an elongation at break of 50%,and a monofilament fineness of 1.10 dtex.

What is claimed is:
 1. A method for preparing a fiber for a medicalantibacterial fabric, comprising: cooling an antibacterial polyestermelt by ring-blowing after extruded from a trilobal spinneret hole on aspinneret, and manufacturing a fully drawn yarn (FDY) according to anFDY process, then performing a relaxation heat treatment to obtain thefiber for the medical antibacterial fabric; wherein a ratio of lengthsof three leaves from a same trilobal spinneret hole is1.0:(1.5-2.5):(1.5-2.5), while widths of the three leaves are same,wherein a ratio of a length to a width of a shortest leaf is(2.5-3.5):1, and an angle between center lines of two adjacent leaves is120; wherein shapes and sizes of three leaves from different trilobalspinneret holes are same; wherein all the trilobal spinneret holes aredistributed in concentric circles, and a direction of the shortest leafin each trilobal spinneret hole is randomly distributed; wherein thering-blowing cooling has a cooling temperature of 20-25° C. and acooling wind speed of 1.80-2.30 m/s; wherein the fiber for the medicalantibacterial fabric has a three-dimensional crimp shape, and in abundle of filaments, crimp directions of monofilaments are inconsistent.2. The method of claim 1, wherein the antibacterial polyester melt hasan intrinsic viscosity of 0.50-0.55 dL/g.
 3. The method of claim 2,wherein the antibacterial polyester melt mainly consists of a polyesterand an antibacterial agent dispersed in the polyester, wherein theantibacterial agent is a silver-based antibacterial agent with a contentof 100-300 ppm of silver ions.
 4. The method of claim 3, wherein the FDYprocess involves technological parameters: a spinning temperature of270-280° C., a first godet roller speed of 1800-2000 m/min, a firstgodet roller temperature of 85-95° C., a second godet roller speed of2700-2900 m/min, a second godet roller temperature of 150-170° C., and awinding speed of 2640-2830 m/min.
 5. The method of claim 1, wherein therelaxation heat treatment has a temperature of 90-120° C. and a time of20-30 min.
 6. A fiber for a medical antibacterial fabric prepared by themethod of claim 1, wherein the fiber for the medical antibacterialfabric has the three-dimensional crimp shape, and comprises a pluralityof antibacterial polyester monofilaments with trilobal cross-section. 7.The fiber for the medical antibacterial fabric of claim 6, wherein thefiber for the medical antibacterial fabric comprises mechanicalperformance indices: a crimp shrinkage of 26-29%, a crimp stability of78-82%, a shrinkage elongation of 55-62%, and a crimp elastic recoveryrate of 70-75%.
 8. The fiber for the medical antibacterial fabric ofclaim 6, wherein the fiber for the medical antibacterial fabriccomprises mechanical performance indices: a breaking strength of 2.4-2.6cN/dtex, an elongation at break of 55.0±5.0%, and a monofilamentfineness of 1.00-1.50 dtex.
 9. The fiber for the medical antibacterialfabric of claim 6, wherein during a preparation of the fiber, theantibacterial polyester melt has an intrinsic viscosity of 0.50-0.55dL/g.
 10. The fiber for the medical antibacterial fabric of claim 9,wherein during the preparation of the fiber, the antibacterial polyestermelt mainly consists of a polyester and an antibacterial agent dispersedin the polyester, wherein the antibacterial agent is a silver-basedantibacterial agent with a content of 100-300 ppm of silver ions. 11.The fiber for the medical antibacterial fabric of claim 10, whereinduring the preparation of the fiber, the FDY process involvestechnological parameters: a spinning temperature of 270-280° C., a firstgodet roller speed of 1800-2000 m/min, a first godet roller temperatureof 85-95° C., a second godet roller speed of 2700-2900 m/min, a secondgodet roller temperature of 150-170° C., and a winding speed of2640-2830 m/min.
 12. The fiber for the medical antibacterial fabric ofclaim 6, wherein during the preparation of the fiber, the relaxationheat treatment has a temperature of 90-120° C. and a time of 20-30 min.